Younger Sister Monica: Chi Soo is struggling to survive medical school life due to his family situation. In his school days, Chi Soo lived in his old friend Song Eun Cheol's house, but naturally became close to Song Eun Soo, Eun Chul's younger sister, and they got married. However, love too is brief... In his second year of marriage Chi Soo experiences a period of ennui, and meets Monica Jeong (Jeong Soo Hee). Monica Jeong impersonated herself as an international lawyer in the United States and came to Korea, and introduced herself as the only child of a wealthy family.